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The garlic fructan (Garlic fructan) garlic residues discarded after the main component of the deep processing of garlic, the molecule of fructose and glucose ratio is about 15:1, and fructose to P-2, 1 and P-2, 6 glycosidic bond connection. A composition of fructose (85%), glucose (14%), galactose (1%). Degradation the garlic residue obtained mainly fructose syrup is not only a comprehensive utilization of waste deep processing of garlic, and a new way to get the high-fructose corn syrup. This thesis, using the enzyme preparation marxianus yeast prepared as well as commodity sucrose enzyme preparation the garlic residue hydrolysis process of high-fructose corn syrup. The results are as follows: (1) study the optimum conditions, Kluyveromyces marxianus Fermentation and enzyme preparations for the preliminary separation and purification. By single factor test and three significant influence factors of nutrients carbon, organic nitrogen, inorganic nitrogen, salt ions, as well as the temperature of the fermentation conditions of pH, inoculum size, time response surface test to determine the highest production inulinase activity conditions: of inulin 1%, 1.51% yeast extract, diammonium phosphate 0.5%, 0.05% zinc sulfate, inoculum size, 6.32%, temperature 30 ° C, fermentation time 72 h, pH 6.5, resulting endo-inulinase enzyme activity 39.16 U / mL, exo-inulinase activity was 94.57 U / mL. (NH4) 2S04 salting out, dialysis and freeze-dried to obtain relatively pure inulin exonuclease, when (NH4) 2S04 concentration of between 40% to 80%, can be precipitated inulin exonuclease. (2) marxianus yeast enzyme preparation prepared hydrolyzed the garlic residue, and optimize the enzymatic process conditions. 5 single temperature, enzyme activity, substrate concentration, pH, and time factors on the efficiency of hydrolysis and orthogonal design obtained optimal solution: pH 4.8, temperature 45 ° C, substrate concentration 9 mg / mL enzyme activity volume 53.95 U / mL, and the time of 8 h, the hydrolysis rate reached 96%. Differential refractive index analysis by high performance liquid chromatography (High performance liquid chromatography, HPLC) method - can know, enzymatic liquid fructose. (3) two commodities sucrose the enzymatic hydrolysis garlic fructan, single factor experiment and orthogonal experiment to determine the sigma sucrase hydrolysis rate higher. The optimum hydrolysis conditions: pH 4.8, temperature 45 ℃, substrate concentration 8mg/mL, enzyme dosage 210 U / mL, time 12 h. In this enzymatic hydrolysis conditions, sucrase hydrolysis rate reached 80%, the main analysis of the hydrolysates by ion chromatography (Ion chromatography, IC) to fructose and glucose. (4) Sigma Company invertase immobilized D201 strongly basic macroporous anion exchange resin to determine the immobilized invertase, optimum temperature, pH and stability. Use of a continuous reaction device Enzymolysis garlic fructan, the results as follows: temperature of 55 ° C, pH 5.0,10% concentration, 0.4 mL / min flow rate, continuous degradation of 4 d, garlic fructan degradation rate of 85% , by calculation, the the immobilized invertase attenuation coefficient kd = 0.0241, operating half-life t1 / 2 = 27d. (5) degradation by comparing inulinase and invertase garlic residue Process, drawn fermentation inulinase hydrolysis rate is high, up to 96% the hydrolysates high fructose corn syrup is a fructose-based. So the garlic slag is a new type of raw material for the production of high fructose corn syrup.
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